[The eight most-played Xbox Live games of the holiday season were all sequels, according to gaming social network GamerDNA -- and the first part of this Gamasutra-exclusive data analysis reveals player usage trends around both titles in the Gears of War franchise.]

The NPD recently revealed sales numbers for the biggest titles of year's end, showing significant sales for games including Gears of War 2, Call of Duty: World at War, and Nintendo's stalwart Wii favorites.

But sales are only a small part of a title's real success -- in which actual playtime and engagement plays a role much harder to quantify.

Gaming social network GamerDNA, which lets users track and share play time, progress and achievements on networked titles, also acts as a database that studies player trends for the benefit of developers.

GamerDNA polled some 150,000 Xbox Live users to find out which games were the most popular over the holiday season, and found that some of the most-played titles within its userbase were sales chart-toppers -- and yet some of them weren't.

A clear pattern emerges -- all of the most-played titles of the holiday season were sequels, with a debut original IP title not to be seen among the top ten.

"People moan about derivative garbage, but when their hind ends hit the couch, they want something they already know they’re going to enjoy," says GamerDNA community analyst Sanya Weathers.

But the stats bear closer inspection -- is the popularity of sequels driven by brand recognition or by their authenticity compared to their predecessors? Can they continue to gain market share?

Using the GamerDNA membership database, analyst Weathers took a closer look at four "gaming powerhouse" franchises over time -- Call of Duty, Gears of War, Guitar Hero and Rock Band to see what insights she could glean about sequels, and Gamasutra will be exclusively publishing insights from her results.

Gears 2 Less Played Than Original?

"First, we looked at a traditional shooter and sequel scenario," says Weathers. "Gears of War was a well-reviewed, well-received game with solid sales numbers -– it hit five million copies sold in September of 2008. Since its launch in November of 2006, 77 percent of GamerDNA’s Xbox 360 owners have played it. It offered a multiplayer component, which served to keep the title fresh in the minds of the playing community."

"Gears 2 was designed and executed by the same studio that designed the first one, and launched exactly two years after its predecessor. With only two months of data, it’s a bit early to call any trends," she says. "But it was as well reviewed as the first one, and had the power of being a known franchise boosting early numbers."

Weathers pulled data on both Gears titles on the 54th day after the sequel's launch and found that 43.4 percent of the sample had tried the new title.

But by day 54 of the original Gears' lifespan, 74 percent of the study population had played it. Weathers characterizes the GamerDNA audience as "early adopters" as one possible explanation for the stronger response to the franchise when it was new.

DLC Wellspring Not Limitless

Notably, the following line graph shows the number of members playing per day since release:

"The peaks all coincide with releases of downloadable content," says Weathers. Surprisingly, she finds that the DLC provided diminishing returns, and that the engagement wellspring DLC promises can run dry over time: "The peaks got smaller, and the boosts lasted for less time each time that bucket went to the well," she says.

"Furthermore, the first map pack for Gears 2 does not seem to have had any effect on play time at all," adds Weathers.

The Sequel Effect

As is to be expected, Gears 2 took a big chunk out of its predecessor's usage. Also very notable is the launch of Halo 3 in September 2007, according to Weathers -- an anomalous dip in March 2007 was due to an Xbox Live crash, and not reflective of the game.

Looking more closely, Weathers says 12 percent of the sampled audience who played Gears 2 never played the first one. And just slightly more than 50 percent of original Gears players haven't yet tried the sequel.

Is there anything to learn from players who've bought and played both titles? "Well, we can definitely put them into two groups -- people who played the first Gears Of War title all the way up to the release of the sequel, and those who did not," Weathers notes.

In fact, 76 percent of the GamerDNA membership who played the first Gears were no longer actively playing it at the time the second one launched.

"We can’t know the reasons, although we can fairly speculate that many of them had played the single player game, finished it for their purposes, and moved on to other games," Weathers suggests.

"Since we’re talking about a group that liked the first one well enough to buy the second one, this lack of engagement is not a problem for the game’s publisher."

The second group includes those still actively playing the first Gears when the second one launched.

As the chart shows, more than 85 percent of players who logged into the original Gears Of War all the way up to the sequel's launch date have left the original in the past -- only a little more than 5 percent ever went back. Just 10 percent of players play both titles.

In our next Gamasutra-exclusive installment, Weathers and GamerDNA will examine the Call of Duty franchise -- specifically the transition from the fourth to the fifth installment -- to see how the franchise's playing habits have changed over the past couple of years.